Password Generator

Generate strong, secure random passwords with custom length and character sets.

Reviewed March 2026 How we build our calculators →

Password Length

Number of Passwords

Uppercase (A–Z) Lowercase (a–z) Numbers (0–9) Symbols (!@#$...)

Generated Passwords

Strength

Possible Combinations

The Formula

Formula

Entropy (bits) = log₂(Characters in set) × Password length

Character sets:
Lowercase only: 26 · + uppercase: 52 · + numbers: 62 · + symbols: 94

Worked Example

12-character password · all character types (94 chars):
Entropy = log₂(94) × 12
= 6.55 × 12
= 78.6 bits — very strong

What Makes a Strong Password?

A strong password is long (16+ characters), random, and uses a mix of uppercase letters, lowercase letters, numbers, and symbols. It should not contain dictionary words, names, or personal information. A 16-character random password from all character types provides approximately 95^16 ≈ 4.4 × 10^31 possible combinations.

Password Security Tips

Use a unique password for every account. Use a password manager (like Bitwarden, 1Password, or Dashlane) to store them. Enable two-factor authentication (2FA) wherever available.

Frequently Asked Questions

How long should my password be?

Security experts recommend at least 12u201316 characters. With modern GPUs, an 8-character password can be cracked quickly. A 16-character random password would take billions of years with current technology.